Oxidative state and quality of pear fruits variety beurre d'anjou with a "blush"

Beurre D'Anjou pears have green skin, sometimes with a reddish patch or 'blush' due to sun exposure. Fruits with a blush are commercially suitable and submitted to similar post-harvest handling procedures than those whose skin colour is completely green. The aim of this work was to compare the oxidative metabolism and changes in quality parameters of pears var. Beurre D'Anjou with a 'blush' to those with completely green skin. At harvest, quality parameters of green and blush areas of sun-exposed fruit were evaluated. Superficial colour, chlorophyll content, anthocyanins and oxidative status were determined on the skin. The blush area presented higher firmness (67.7 N), soluble solids content (13.4 degrees Brix), starch degradation (38%) and malic acidity reduction (0.25%) compared to the green area, with values of 61.9 N, 12.0 degrees Brix, 26% and 0.47% for each parameter, respectively. The HUE degrees angle was 73.9 in the blush area and 123.9 in the green area. This smaller HUE degrees angle expresses the reddish colour associated with an increase in anthocyanin content. Compared to the green area, the blush area recorded an increase of 59.7% in lipid peroxidation and 55.2% in antioxidant capacity. Significant differences were found between the fruits with a blush and those with completely green skin in terms of quality parameters and oxidative state, regardless of the fact that both of them developed under similar sun exposure conditions.